Combined electrically-mechanically operated clock



Feb. 16, 1954 c. R. BOYD 2,669,088

COMBINED ELECTRICALLY-MECHANICALLY OPERATED CLOCK Filed Feb. 14, 1949lluhminr CLYDE R BOYD.

Patented Feb. 16, 1954 UNITED STATES PATENT OFFICE COMBINEDELECTRICALLY-MECHANICAL- LY OPERATED CLOCK Clyde E. Boyd, Baltimore, Md.

Application February 14, 1949, Serial No. 76,231

2 Claims. 1

This invention relates to horological instruments and more particularlyto a combination of electrically-mechanically operated mechanism forclocks. The invention has among its objects to provide a new andimproved electrical-mechanical horological mechanism that will avoid oneor more of the disadvantages and limitations of the prior art.

Another object of the invention is to provide a new and improvedhorological mechanism that can intermittently operate eithermechanically or electrically.

A further object is to provide a new and improved horological mechanismthat can automatically actuate alternately mechanically or electricallyas conditions may require.

An additional object is to provide a new and improved electrical clockthat will operate electrically normally but in case of stoppage of theelectrical source of current will automatically shift to mechanicaloperation and continue in this manner for a considerable period, and besubject to its return to electrical operation when the service for suchis restored at any time. Other objects will be evident as the inventionis further outlined.

In the conventional type of electrical clock, the operation is subjectto the continuance of the electrical service supplying same. Should itbe interrupted for any reason, the clock will stop at that moment, andstay stopped until the service is restored. On restoration, the clockmay restart automatically or may require manual restarting depending onthe type of clock used. In any case, the time on the clock at restartingwill be that at which the original stop occurred. This is objectionableas it requires thev resetting of the clock hands to put them on time. Ifseveral hours have elapsed in between, the clock hands will be delayedby that amount, and if the fact of the inaccuracy is not appreciated maycause considerable inconvenience to those who rely on the time indicatedas being correct. In this invention the clock is operated normally orprimarily by electrical current. However, when such is interrupted, itautomatically shifts to conventional mechanical or auxiliary operationas long as necessary, without stopping the hands of the clock for anynoticeable amount, and then when the electrical service is resumed,returns to electrical operation automatically, without stopping thehands. This it will do indefinitely or until themechanical mechanismneeds rewinding.

.For a-more detailed description or the invention, its principles andoperation, reference is made to the accompanying drawings wherein aparticular form is indicated by way of example. These drawings areexplained in the following specifications, while the scope of theinvention is emphasized in the claims.

Referring to the drawings:

Figure 1 is a front view of a clock embodying this invention;

Figure 2 is a side elevation of Figure 1, with parts broken away to showthe electrical and mechanical construction of the horological mechanismused in this embodiment; and

Figure 3 is a diagrammatic arrangement showing operating parts of clockset out in Figures 1 and 2.

Similar reference characters pertain to the same parts throughout thedrawings.

In the particular form of construction shown in the drawings aconventional clock housing i0 is employed, with a dial ll marked witharabic numerals l2 or time indicators spaced appropriately along itsperipheral area, together with such hour and minute markings as may bedesired to make the reading of the time convenient. The minute hand l3and hour hand I 4 are of conventional design and operated about thecenter of the dial, through such operational elements as are necessaryfrom the clock mechanism mounted within the housing.

The mechanism used for operating the hands is in two sections, l5 andI6, termed mechanical and electrical mechanisms respectively and in thisinstance coupled to one another. They are also termed the primary andauxiliary motive sections.

Primarily the electrical mechanism of section is is of conventionalform, including a train of gears I9 operated by an electrical motor 20,a frame 2| to support the gears and parts, and the shafts 22 and 23concentrically arranged for operating the hour and minute handsrespectively. In addition an electro-magnet 24 is mounted on the frame2! with its coil 25 energized in parallel by the same circuit supplyingcurrent that flows from the service connections 26 to the motor 20. Themagnet 24 is not effectively energized when the current is disconnectedfrom it.

This magnet 24 is employed for operating the clutch mechanism 21 thatcouples the mechanical mechanism [-5 with the electrical mechanism Thisis accomplished by a pring 28 tensioned to throw the clutch 21 intoaction when the magnet is deenergized. This clutch mechanism 21 does twothings, first it operatively couples the train of gears 29 of themechanical mechanism with the train of gears I9 of the electricalsection so it will continue to actuate the hands I 3 and I 4, as ifdirectly connected with them, and secondly it releases the brake 30 sothe clock main spring 3I will be able to operate the gear train 25}without hindrance. This brake 3B is used to hold the mechanism ofsection I5 against operation until' the electrical source fails. Theelectrical connections to the electrical motor 20 are not disturbed bythe clutch 21 or brake 30. The motor 20, its gear train I9 and hands I3and I4 are all operated without change by the mechanical mechanism whenthe clutch is connected and brake released. The mechanical mechanism, isof conventional clock type and has the main spring 3I attached to itsframe and its train of gears 29 in a conventional manner. It is wound upby a key 32 on the shaft 33, with ratchet and pawl elements suitablycon.- nected. Preferably the spring 3I is of th eightday type, so itwill be long operating and able to meet exceptional emergency service.In such an instance, the spring would be available for several years usewithout rewinding, under ordinary conditions.

Th magnet 24 is placed in an accessible location on the frame 2|, and anarmature 35 mounted on a hinged arm 36 is placed where it can beenergetically drawn towards the magnet poles when the latter areenergized through the use of the coil 25. When the arm 36 is so pulled,the electric servic operates the motor 20 also, without any resistancefrom the mechanical mechanism I5. However when the electric serv* ice isinterrupted, the magnet 24 is" deenergized. The arm 36 under the tensionof the spring 28 is then pulled away from the magnet. The arm 36 carriesa fork 31 that holds a loose half 39 of the clutch 27, it is moved bythe spring 28 until it engages the rigid half M of the clutch mechanismand couples both the mechanical and electrical units operably together.When the clutch mechanism 21 is so coupled and the train of gears 29 isactuated, the electrical mechanism I6 is physically rotated. thereby'bythe mechanical mechanism I5. 4 rectangular sectional piece AI is rigidlymounted on the extending shaft d5 of the escapement wheel 43 whichincidentally is connected in the train of gearing 29. The part ll is soaligned with a socket joint 52 mounted on the arm 34; that the lattercanslide readily off of it when the arm 36 is released by the ma net 24.When this socket G2 is saddled on the 41 t ks th ent wheel c 5 it a notrotate and this in' turn loclgs andstops the whole t a n 9 f the mec n a'riich m 5- When the socket joint l? is removed or unloosened from theescapement wheel shaft 45 of the mechanical train becomes operable inthe conventional'way by its main spring 3|, This: is what happens whenthe magnet is deenergiz ed and allows the arm 36 to be pulled up by itsspring 28 and engages the clutch 2? and operatesthe hands until thecurrent comes back to operate the motor 29. A peg M limits the movementof the arm 36 and keeps the armature 35 within the influence of thefield of the magnet 24.

When the magnet 24 is energized by the current being restored at theservice, it attracts the armature. This incidentally pulls the arm 36 sothe mechanical clock mechanism is disconnected from the electric clockmechanism I 9 and-stopped by the brake 30. The current fiowingthroiighthe motor 20 operates it and actuates the clock mechanism directly byelectrical current, and is entirely free of the mechanical mechanism.The operational elements of the clock movement are those parts orextensions that are included for supporting the hands operably.

Thus when the primary electrical service current is interrupted themotor 29 is electrically disconnected and the electrical mechanism I6 issimply a mechanical part of the clock system for the time being, and themechanical clock movement I5 with spring 3! take over to turn the handsis and Id using the mechanism I9 as an intermediate coupling. This isarranged by the clutch mechanism 21 tieing the two mechanisms I5 and I6together and the brake 30 being released. so the main spring canactivate the system to turn the hands. The reestablishment of theelectrical service, immediately connects the electrical mechanism I6back into operation. This disconnects the auxiliary mechanical sectionI5, whilev at the same time stopping it, so the clock runs entirely onthe electrical mecha: nism Is in a conventional manner. Should thespring 3| operate so many times as to use up all its potential energy byits unwinding sufficiently, itbecomes necessary for the user to rewindthe main spring SI again. Since this rewinding may not be necessary forseveral years and only takes about a minutes time, it becomes a minoritem to be considered. It is of course understood that the mechanisms inboth instances operate at such periods of time as to make the handsrotate around the clock in the same time and apporr tion their movementsto suit the hours etc. marked or space-d on the clock; face card. It isalso understood that the term gear train can include any secondaryauxiliary mechanism suitable for horological use that will change thespeed of the electrical motor andthe spring wound motor to suit therotation suitable for moving the hands around the clock face, and thatgears themselves with teeth are not essential, since such operation cantake place through th use of frictional contacts, chains or belts andsimilar means just as efiectively. It is further understood that aconventional synchronous motor as conventionally used in electric clockscan be used and coupled to the mechanical mechanism I5 through clutch2'! and arm 3% and yoke 3? as explained above.

However since it does not appear that the prior art appreciated theintrinsic value of employing an auxiliary motive section for emergencyoperation when the primary clock section becomes inoperative, it isfurther intended that the application will embrace the field ofsecondary operation broadly, whether the auxiliary section be strictlymechanical in its usual sense or interpretation of the term or not. Thisis due to the fact that the secondary motive section could includeelectrical or even chemical motive mechanism to operate it, withoutexceptional ingenuity on the partof designers anticipating to employ theprinciples of this invention. In such an instance a battery and motor inits circuit would be used to operate the auxiliary section when theprimary motive sectionfailed. Also, it would be feasible to provide amodified clutching arrangement for operating the hands directly, whenthe primary section failed instead of including all the mechanism of thelatter. It is however essential in this invention'that the hands of theclock forindieating the time register their positions similarly for thesame hours'and'minute'ano matter which motive section is actuating them.Also further sequential operational sections could be provided in casethe first auxiliary section also failed, if such a requirement wasinvolved in the conditions of use, to anticipate progressive break downsand more positive continuance or non-interruptional performance of theclock operation.

While but one general form of the invention is shown in the drawings anddescribed in the specification, it is not desired to limit thisapplication for patent to this particular form, as it is appreciatedthat other forms of construction could be made that would use the sameprinciples and come within the scope of the appended claims.

Having thus described the invention, what is claimed is:

1. In a clock, time indicating means, a synchronous motor, a train ofgears between said time indicating means and said motor, a spring motor,driving means between said spring motor and the aforesaid train of gearscomprising a second train of gears driven by the spring motor, saidlast-mentioned train of gears including an escapement wheel and a shaftextending therethrough, and a clutch between said last-named train ofgears and said first train of gears, means for operating said clutchincluding a pivoted lever, a magnet in parallel with the electric motorcircuit to swing said lever about its pivot, and locking means for saidescapement shaft carried 6 by said lever to immobilize said shaft whenthe clutch disconnects said driving means from said first train ofgears.

2. In a clock, time indicating means, a synchronous motor, a train ofgears between said motor and said time indicating means, a spring motor,gearing and shafting between the spring motor and the aforesaid train ofgears, said shafting including the escapement wheel shaft, a clutchbetween the aforesaid train of gears and the gearing and shafting, meansfor operating said clutch, and cooperating locking means be tween theescapement wheel shaft and the clutch operating means for immobilizingthe spring motor, consisting of a socket carried by the clutch operatingmeans and an extension carried by the escapement wheel shaft receivablein the socket.

CLYDE R. BOYD.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,072,609 Taliaferro Mar. 2, 1937 2,079,029 Neureuther May 4,1937 2,228,825 Hernandez Jan. 14, 1941 FOREIGN PATENTS Number CountryDate 511,327 Great Britain Aug. 16, 1939

